Nocturnal disturbances such as wandering, day/night confusion, getting out of bed repeatedly, engaging in inappropriate activities, hallucinations, talking or singing in bed, and increased confusion are very common in persons with Alzheimer's disease (AD). Being awakened at night has been identified as one of the most disturbing aspects of dementia caregiving. It is associated with increased physical and psychological morbidity in both patients and caregivers, and is a major risk factor for patient institutionalization. Despite the fact that over 70% of demented individuals live at home and are cared for by family and friends, there has been only one controlled behavioral treatment study targeting nocturnal disturbances in community-dwelling AD patients (the Nighttime Insomnia Treatment and Education for Alzheimer's Disease, or NITE-AD study). That study, a pilot conducted by the P.I. of the current application, produced significant reductions in number of patient nighttime awakenings and total time awake at night. A recent NIH task force proposed a set of diagnostic criteria for sleep/wake cycle disturbances in AD patients, and called for research to develop and evaluate non-pharmacological treatments for these disturbances. The proposed study is a response to this call. This study is a randomized controlled trial to evaluate the efficacy of Walking (W), Light Exposure (L), and combined walking, light exposure, and sleep hygiene recommendations (NITE-AD) to reduce nocturnal disturbances in community-dwelling AD patients, compared to Routine Medical Care with Education (RE). Two hundred patients that meet criteria for sleep/wake cycle disturbances in AD and live with a family caregiver will be recruited from a statewide community network of AD patients. Patient and caregiver treatment effects will be assessed at baseline, 1 month, 2 months, and 6-month follow-up. Patient institutionalization rates will be monitored for one year. The primary outcomes will be actigraphic measures of patient total wake time at night, and caregiver reports of patient nighttime behavioral disturbances. Secondary outcomes include caregiver sleep, patient daytime sleepiness and overall level of behavior problems, patient and caregiver mood and health, and patient residential status.